Philadelphia abortion doctor Kermit Gosnell was found guilty today of first degree murder in three of four infant deaths.

Gosnell was also convicted of involuntary manslaughter in the death of a female patient who was given a lethal dose of sedatives and pain killers in 2009, according to the Associated Press.

Gosnell, 72, could face the death penalty and jurors will begin hearing testimony on May 21 to determine if they will condemn him to death row.

The verdict came hours after the jurors alerted the judge that they were deadlocked on two counts. The judge told the jurors to try again for a unanimous verdict.

Gosnell had little visible reaction to the verdicts, Vernon Odom, an ABC News reporter in the courtroom, told ABC News Radio. On the other hand, prosecutors hugged each other upon hearing the verdict.

The decision came on the jury's 10th day of deliberations. It was not clear which of the more than 200 counts in the case, which included racketeering, had deadlocked the jury.

Gosnell's lawyer, Jack McMahon, noted his client was found not guilty on several murder charges and commended the jury.

"They paid attention," McMahon said, according to ABC News Radio. "I mean, they didn't just come down knee-jerk and find him guilty of everything."

However, amid the guilty verdicts, he added, "As any intelligent human being would be at this time, he's disappointed and he's upset."

Gosnell was accused of performing late-term abortions on four babies who were born alive, but were then allegedly killed by Gosnell.

For two months, the jury heard often grisly testimony, including from members of Gosnell's staff. Eight staffers have pleaded guilty to several crimes. Prosecutors said none of the staff were licensed nurses or doctors.

Gosnell ran the Women's Medical Society in West Philadelphia for decades until February 2010, when FBI agents raided his clinic looking for evidence of prescription drug dealing.

Instead they found, as reported in a nearly 300-page grand jury report released in 2011, a filthy, decrepit "house of horrors."

Blood was on the floor, the clinic reeked of urine and bags of fetal remains were stacked in freezers. The clinic was shut down and Gosnell's medical license was suspended after the raid.

Despite repeated complaints to state officials over the years -- as well as 46 lawsuits filed against Gosnell -- investigators said in the report that state regulators had conducted five inspections since the clinic had opened in 1979.

McMahon maintained his client served his community and never killed a live, born baby.

However, the grand jury report in the case said there had been hundreds of "snippings," in which live babies were born and then killed.

"Gosnell had a simple solution for the unwanted babies he delivered. ... The way he ensured fetal demise was by sticking scissors into the back of the baby's neck and cutting the spinal cord. He called that 'snipping,'" the report alleged.

The report also said that many of the women patients were infected with sexually transmitted diseases from contaminated instruments, had suffered from botched procedures or had been given overdoses of dangerous drugs.